Keyhole guard



F. .vv sci-iou KEYHOLE GUARD Filed Nov. 26, 1921 my; [3 H H 6.

FRAN/f W 50H0(/ INVENTOR.

BY RK X ATTORNE ei ir eg Figure 3 is a Patented a. is, 243.

use? FRANK w. SCI-IOU, or LINCOLN, NEBRASKA. Assieivoa rovknn sciio i, or Bones CITY, ansas.

KEYHOLE sunnnf Application filed November 26, 1921} Serial No. 5172880.

Houses. are often entered by thieves and burglars by means 'of p'ass keys. tis well known that most of the mortise and other 5 lockson housezd'oors can be easily unlocked by using a button hook; hair pin, bent wire or other improvised substitute fora key. It rthe doorkeyis left in the'lock; it'can be easily pushed out, orby nieansof long nosed pliersit can be turiied'andn adeto unlock the'door. These troubles occur most .fre-I ueiitl in a artiiientfhouse's hotels and rooming liouseshwhere illitlly ta guest has awakened in the morning to find thathis .100111 had been entered during the night,i v I its keyin the-:usualmaniier and the key is then removed from the key hole. The rod and that money, jewelry, or valuable papers -were missing. My invention gives elfective protection not only when the occupant is in the room but also when he is away.

In the drawings which form apart of this applicationr f V Figure 1' shows a portion of a door with my device applied to the opposite side.

Figure 2 shows a. section of the same door;

threaded rod. and its key way. i

Figure 4 is a detail of the part whiohlis slidably secured tot-herodr Figure 5 is a transverse sectionlofan 3 other form of my invention.

Figure 6 shows in plan the same niodifica tioii, the collar being sectioned to'show the FOG. 7 a l A a I l.

Figure 7 illustrates the key hole guard and i Figure 8 sliows the v The rod 10 is screw threaded throughouta portion oi its length. at 11 and isprovided with a key way 12. A'lug 13 is secured to the end oi? tlierodwhich enters the key hole; The lug projects radially outward from the rod, and isangularly disposed with referdetail viewiof the screw V v collar used with the f modification shown generally in Figures 5' 3 once togthe key way, the preferred aiiglebeii'ig 'aprightangle. .At its free end the, rod 3 tern'iinates in aiiysuitable handle such as a hook (ii-"knob, but-I prefer to use a ring as shown at '14:.

-The key hole closure 15 shown in detail in Figure 7 is preferably formed from two pieces of inetal welded-or otherwise secured together. The outer piece is bent upon itsel't to form a collar 16 and ears 1?. The 1I1-' ternal diameter? ofthe collar is slightly,

greater than the diameter of the rod 10. The inner piece comprises a portion fitting betweenthe earsll; and the inner edge or,

thisport'ion; is a key 18 which'is adapted to fit into the ke iway 12. The lu 19 is integi'al withtheportion between thereara and is ofsueli a length'thatwhen it-is seated in V thekey hole, the lug l9 extendsv nto the path of rotation of the lug 13; I I, v

llhus far thestructure is common toboth forms of my, nventiomand when it is de sired to, secure thelockon the insideof the room, this structure is all that is needed. In

this case the lockboltisthrown by means. of l 10 with its bolt'l? is then thrustjiiito the key hole and given a quarter ofaturn, which brings he l g 19 into alignment with the k y h l Thejkey hole guard 15 is-then proper. Tlie iiollower 20 is then screwed tight.

It will readilybe seen that access through theylock froin the'outside is utterly iinpos-- sible' The key hole guard 15 can not rotate I because of the anchorage of the lug 19 iii the key holebnor can it beshoved length wise againstthe follower 20. t The rod l O be. 1

ing keyed against rotation can not turn whilethe key hole guard is seated in the key hole and even in the almostimpossible event 1 thatthe key sliould yield iii the keywa-y, the lugs l3 and .19would limit therotation toa quarter turii which"would have no appreciable e ifeet lengthwise on the follower together cannot pass out of the key hole at the. saine time; The only poss'ible way to remove my device froiiithe lock is to first 120. In this case the lugs 13 and '19 would" be broughti'nto juxtaposition, andboth lugs .105

unscrew the follower 20, and since this is on the inside of the room, it is impossible to gain access to it through the door.

It frequently happens that the occupant when he leaves his room wishes to secure the look so that the ro'om'can not be entered during his absence. For this reason I have add ed to the fundamental structure other elements which make it impossible to tamper with the follower 20 when the device is ap plied to theoutside of the door. In the construction shown in Figures 2 and 4:, I per-' for-ate the earsl'. of thekey hole guard 15 and pass a pin 21. through the aperturethus formed, firmly, securing the pin in the aperture thus formed. To the two extremities of the pin 'I pivota yoke 22. The follower is provided with a looped element 23 integral therewith. When all of the parts are in place on the door lock the yoke 22 is swung over the loop 23 and a padlock, preferably of the Yale or pin tumbler type,

is secured to the loop. This of course necessitjat'esjin the case ofunauthorlzed entry into the room that the, padlock be first plcked ibei 'ore' access can he gained to the door lock.

v y In the construction shown in'l igures 5, 6,

4, and 8, I accomplish the same result by means of a' slight modification. I perforate the ears 17 M25, the aperture '25 extending through. the portion between the ears. A

sleeVeJQ-J' having ears 27 and ot a size to; 16 and cars 17,, and of a suitable length is added 1 fit snugly but 'slidably over the collar to the equipment. Apertures' 28 in the ears 27 register with the apertures in the ears 17 when the device is in place on the door lock. In use the key hole guard is seated in the key hole, the follower 20 is screwed tight, the sleeve 26 is shoved into position, and a pad lock 24 is secured through the apertures 25 and 28, thus making access to the follow- 20" virtually impossible.

Having thus described my invention and the method of using it what I claim as new and desireto secure by Letters Patent of the Un ted States 1s:-

A key-hole guard comprising a stem which is adapted to enter key-hole, a lug keyway of the stem to prevent rotation of the yoke on the stem, said yoke also being provided with a lug'integral therewith, said last named lug being adapted to, enter the key hole and to extend into the path of rotation of said first named lug, a screw thread v on said stem, a screw-threaded follower surrounding saidstem, a second yoke which is. adapted to surround said first named yoke and said follower, and apertures in both of said yokes, the arrangement beingsuch that when the keyhole guard is in place in the lock, the apertures in the two yokes will register for the reception of a padlock.

In testimony whereof I atlix my signature.

FRANK W. sonou 

